I just installed multisite on my windows locally hosted bitnami server, using the instructions from your video. I also deactivated all plugins before installing multisite.
I just ran into the blank screen problem. Kind of like previos thread
I type in localhost/wordpress and just a blank screen loads up.
I type in http://localhost/wordpress/wp-login.php and the login comes up.
I try and login and blank screen again, try getting into wp-admin and you guessed it blankscreen.
I was using notepad ++ and also was forced to use sub directories because I was on a localhost.
I also got nothing but blank screen when I turned on debug.